[R] computing distance in miles or km between 2 street addresses

[Philip James Smith]

Hi R-ers:

I need to compute the distance between 2 street addresses in either km 
or miles. I do not care if the distance is a "shortest driving route" or 
if it is "as the crow flies."

Does anybody know how to do this? Can it be done in R? I have thousands 
of addresses, so I think that Mapquest is out of the question!

Please rely to: philipsmith at alumni.albany.edu

Thank you!
Phil Smith